When using images from Picture Stock Worldwide, Inc., it is important to review the specific licensing agreements associated with each image, as the requirements may vary. Typically, images from stock agencies come with certain terms and conditions that specify whether attribution or credit is necessary. In many cases, stock images do not require crediting the source, allowing users more flexibility in their projects. However, some licenses may include stipulations that require users to give credit to the creator or agency. To ensure compliance with the licensing terms, it is advisable to read the details provided on the current webpage where the images are accessed. This will provide the most accurate information regarding crediting and any other usage policies specific to Picture Stock Worldwide, Inc. Always be diligent in understanding the requirements before using any images.